INGENIEUR
Indah Water Konsortium Sdn Bhd (IWK) is
the national sewerage company in Malaysia
which started operating in 1994 and is today
managing close to 7,000 sewage treatment
plants (STPs), 1,200 network pumping stations
and 20,000km of sewers serving a 26 million
population equivalent. Undoubtedly, these
amassed assets are evidence of the immense
planning and engineering efforts that have
taken place over the years and are a testimony
to the design and construction expertise in the
sewerage industry in the country (see Figure 1).
The STPs spread across the country embrace
numerous systems including: commonly
activated sludge, extended aeration, sequencing
batch reactors (SBRs), moving bed biofilm
reactors (MBBRs), etc. The different treatment
systems clearly demonstrate the progression and
technological transformation in the sewerage
industry over the years (see Figure 3).
The development and construction of STPs
may involve construction on green field or
brown field sites which can be developer driven
or through investment by the Government. In
sewerage systems, the following types of pipes
are widely utilised: reinforced concrete, vitrified
clay and ductile iron pipes. The methods in
laying a sewerage pipe can vary from open cut to
trenchless techniques (see Figure 2) depending on
the ground conditions, site constraints or governing
requirements. The network pumping stations are
made up of submersible and dry-well types.
Multiple engineering disciplines are involved
in the sewerage industry including civil,
mechanical, electrical, chemical, environmental,
bioprocess, biochemistry, systems engineering,
etc. In addition, many component parts of the
sciences are involved including; micro-biology,
chemistry, physics, resource planning and the art
of engineering and construction in the sewerage
industry.
Various elements of engineering in the
construction and development of the sewerage
systems are displayed in on-site toilet systems,
internal plumbing, sewer networks, pumping
stations, ranging types of sewage treatment
Figure 1: Evolution of Sewerage System in Malaysia
32 VOL 81 JANUARY-MARCH 2020